Historically, panels for dividing office or other space have been wrapped in fabric by premeasuring the fabric, sewing it into a tube with one seam, placing it upon a stretching device and then inserting the panel core inside the tube, removing the stretcher and finishing the ends of the panel. It is imperative to understand that for good appearance the fabric must be in tension. This method required that the panel be perfectly rectangular, i.e. all right angles, the seam be very straight and that the fabric not be stretched beyond its elastic limit.
Examples of devices for placing material under tension such that they may be secured as a skin include:
U.S. Pat. No. 2,342,025 granted to Watter, Feb. 15, 1944, which discloses an apparatus for placing metallic skin under tension and then applying it to the framework of an airplane or the like.
U.S. Pat. No. 2,804,101 granted to Johnson et al., Aug. 27, 1957, discloses an apparatus for tensioning a screening material and then applying it to frames.
U.S. Pat. No. 3,041,109 granted to Eames et al., June 26, 1962, discloses a method for securing a fabric material to a framework by inserting it into a slot and then securing it in place.
U.S. Pat. No. 3,699,626 granted to Roth et al., Oct. 24, 1972, discloses an apparatus for automatically placing a fabric over a framework for a small object such as a brush for removing lint from clothing or the like.
U.S. Pat. No. 3,777,347 granted to McCorbey et al., Dec. 11, 1973, discloses an apparatus which draws two parallel sheets of material such as sheet metal through a dye-forming means and then sprays material into the space between the sheets of metal such that when it is cured it fills the space between the sheets.
U.S. Pat. No. 3,840,960 granted to Toti et al., Oct. 15, 1974, discloses an apparatus for forming hollow metallic beams and the like by simultaneously forming the individual panels and then sealing them along the edges.
U.S. Pat. No. 3,851,684 granted to Wyrach et al., Dec. 3, 1974, discloses an apparatus for assembling flexible sheet material into window screens or the like by securing the material to the frames without rotating the frames.
U.S. Pat. No. 4,147,582 granted to Brollo, Apr. 3, 1979, discloses an apparatus for continuous production of prefabricated insulating panels of sheet metal including a rolling mill and a device for injecting a expandable foam plastic material between the skins.
U.S. Pat. No. 4,257,150 granted to Heffner et al., Mar. 24, 1981, discloses an apparatus including means for providing sheet metal from two separate rolls, a pair of structural assemblies including clamping jaws and means to move the material to a position for fastening.
U.S. Pat. No. 4,426,760 granted to Watts et al., Jan. 24, 1984, discloses a tool for rolling sheet material into a retaining slot.
U.S. Pat. No. 4,516,305 granted to Unger et al., May 14, 1985, discloses a method of/and structure utilized, in securing upholstery fabric to a chair or the like and by utilizing bars under tension to retain the fabric in position.